New Delhi: After questions were raised over the cause of a constable's death during violent protests over gang rape last Sunday, the Delhi Police on Wednesday assigned its Crime Branch to investigate the case in which murder charges have been invoked.

Constable Subhash Tomar (47) died on Tuesday, three days after suffering injuries at India Gate where violence had erupted during protests against the gang rape of a 23-year-old girl in a moving bus in south Delhi on December 16, police had said.

"The case has been transferred to the Crime Branch," Delhi Police spokesperson Rajan Bhagat said. He did not provide reasons for transferring the case from New Delhi district police to the Crime Branch.

However, sources claimed that New Delhi district police will be busy in the coming days with regard to preparations for the Republic Day parade and maintaining law and order.

Questions were raised over the cause of Tomar's death with a journalism student, who claimed to be an eye-witness, countering the police version that the Constable was injured in the violence.

The police have slapped murder charges in the case. Earlier, eight persons were arrested on Monday on charges of attempt to murder.

On Tuesday, Police Commissioner Neeraj Kumar had said that Tomar had suffered internal injuries in neck, chest and stomach and the police were waiting for post-mortem report for the exact cause of death.